Reapply an improved version of r180816/180817.

Change the informal convention of DBG_VALUE machine instructions so that
we can express a register-indirect address with an offset of 0.
The old convention was that a DBG_VALUE is a register-indirect value if
the offset (operand 1) is nonzero. The new convention is that a DBG_VALUE
is register-indirect if the first operand is a register and the second
operand is an immediate. For plain register values the combination reg,
reg is used. MachineInstrBuilder::BuildMI knows how to build the new
DBG_VALUES.

rdar://problem/13658587

llvm-svn: 185966

1 files changed, 9 insertions, 7 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 3d490fac6b2..98879649c81 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -421,12 +421,13 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
       MachineBasicBlock::iterator InsertPos = Def;
       const MDNode *Variable =
         MI->getOperand(MI->getNumOperands()-1).getMetadata();
-      unsigned Offset = MI->getOperand(1).getImm();
+      bool IsIndirect = MI->getOperand(1).isImm();
+      unsigned Offset = IsIndirect ? MI->getOperand(1).getImm() : 0;
       // Def is never a terminator here, so it is ok to increment InsertPos.
       BuildMI(*EntryMBB, ++InsertPos, MI->getDebugLoc(),
-              TII.get(TargetOpcode::DBG_VALUE))
-        .addReg(LDI->second, RegState::Debug)
-        .addImm(Offset).addMetadata(Variable);
+              TII.get(TargetOpcode::DBG_VALUE),
+              IsIndirect,
+              LDI->second, Offset, Variable);
 
       // If this vreg is directly copied into an exported register then
       // that COPY instructions also need DBG_VALUE, if it is the only
@@ -445,9 +446,10 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
       if (CopyUseMI) {
         MachineInstr *NewMI =
           BuildMI(*MF, CopyUseMI->getDebugLoc(),
-                  TII.get(TargetOpcode::DBG_VALUE))
-          .addReg(CopyUseMI->getOperand(0).getReg(), RegState::Debug)
-          .addImm(Offset).addMetadata(Variable);
+                  TII.get(TargetOpcode::DBG_VALUE),
+                  IsIndirect,
+                  CopyUseMI->getOperand(0).getReg(),
+                  Offset, Variable);
         MachineBasicBlock::iterator Pos = CopyUseMI;
         EntryMBB->insertAfter(Pos, NewMI);
       }